On the basis of the results obtained in the previous year, 4 main lines of research are proposed: 1) Further characterization of the mode of action of previously identified selective antimetastatic agents with emphasis on their effects on the activity of macrophages and other immunocytes; 2) Further exploration of the therapeutic potential of combined approaches with binary or multiple combinations of selective antidisseminative compounds - anticoagulants - passive specific and active non specific immunostimulants in micrometastasis models; 3) Further dissection of the interrelations between cancerous dissemination and blood coagulation in syngeneic models of spontaneous metastatization with emphasis on the use of drugs having specific activity on the coagulative complex; 4) Investigate the role of suppressor cells in tumor progression and dissemination examining the effects on these elements of antimetastatically active non specific immunomodulators. BIBLIOGRAPHIC REFERENCES: Poggi, A., Polentarutti, N., Donati, M.B., de Gaetano, G. and Garattini, S., Blood coagulation changes in mice bearing the metastasizing Lewis lung carcinoma. Cancer Res. 37, 272, 1977. Poggi A., Donati M.B., Polentarutti N., de Gaetano G. and Garattini S., On the Thrombocytopenia developing in mice bearing a spontaneously metastasizing tumor. Z. Krebsforsch. 86,303,1976.